Methodology

How did we develop our methodology?

Read more about how we measured the number of people in modern slavery, the factors that make them vulnerable, and what governments are doing to respond.

How did we measure prevalence?

Measuring the number of people in modern slavery is a difficult undertaking due to the hidden nature of this crime and low levels of victim identification. Since 2014, we have conducted 25 surveys with Gallup Inc.[1] through their World Poll, interviewing more than 28,000 respondents in 52 languages. This year we also conducted state-level surveys in India. When these are included, we have interviewed more than 42,000 respondents in 53 different languages. The prevalence estimates in the Index are based on data from these surveys, the results of which have been extrapolated to countries with an equivalent risk profile.

[1] Gallup Inc. is an international research-based company, http://www.gallup.com/home.aspx

How did we measure vulnerability?

The Global Slavery Index includes a model of 24 variables which affect vulnerability to enslavement, and cover:

  • Political rights and safety
  • Financial and health protections
  • Protection for the most vulnerable
  • Conflict

Statistical testing identified and grouped these factors due to their relationship to the prevalence of modern slavery.

How did we measure government responses?

The final component of the Index is a score of government responses based on an assessment of 98 indicators of good practice, taking into account factors such as whether each country has the necessary laws in place, provides support to victims, and ensures the application of labour standards to vulnerable populations. Research for this aspect of the Index involved a partnership between the Walk Free Foundation’s research team and DataMotivate, an organisation that provides training and employment for survivors of modern slavery in the Philippines.

A summary of the methodology is in Appendix 2 in the pdf version of the report, and a detailed methodology paper is available to download from the downloads page.

  • Rating
    Numerical Range
    Description
  • AAA
    90 to 100
    The government has implemented an effective and comprehensive response to all forms of modern slavery, with effective emergency and long-term reintegration victim support services, a strong criminal justice framework, high levels of coordination and collaboration, measures to address all forms of vulnerability, and strong government procurement policies and legislation to ensure that slavery is not present in business supply chains. There is no evidence of criminalisation or deportation of victims.
  • AA
    80 to 89.9
    The government has implemented a comprehensive response to most forms of modern slavery, with strong victim support services, a robust criminal justice framework, demonstrated coordination and collaboration, measures to address vulnerability, and government procurement guidelines and/or supply chain policies or legislation to ensure that slavery is not present in business supply chains.
  • A
    70 to 79.9
    The government has implemented key components of a holistic response to some forms of modern slavery, with strong victim support services, a strong criminal justice framework, demonstrated coordination and collaboration, measures to address vulnerability, and may have taken action to ensure that government procurement policies do not encourage slavery.
  • BBB
    60 to 69.9
    The government has implemented key components of a holistic response to modern slavery, with victim support services, a strong criminal justice response, evidence of coordination and collaboration, and protections in place for vulnerable populations. Governments may be beginning to address slavery in supply chains of government procurement, or of businesses operating within their territory. There may be evidence that some government policies and practices may criminalise and/or cause victims to be deported.
  • BB
    50 to 59.9
    The government has introduced a response to modern slavery, which includes short-term victim support services, a criminal justice framework that criminalises some forms of modern slavery, a body to coordinate the response, and protection for those vulnerable to modern slavery. There may be evidence that some government policies and practices may criminalise and/or cause victims to be deported and/or facilitate slavery.
  • B
    40 to 49.9
    The government has introduced a response to modern slavery, with limited victim support services, a criminal justice framework that criminalises some forms of modern slavery (or has recently amended inadequate legislation and policies), a body or mechanisms that coordinate the response, and has policies that provide some protection for those vulnerable to modern slavery. There is evidence that some government policies and practices may criminalise and/or deport victims and/ or facilitate slavery. Services may be provided by International Organisations (IOs)/NGOs with international funding, sometimes with government monetary or in-kind support.
  • CCC
    30 to 39.9
    The government has a limited response to modern slavery, with limited victim support services, a criminal justice framework that criminalises some forms of modern slavery, and has policies that provide some protection for those vulnerable to modern slavery. There may be evidence of a national action plan and/or national coordination body. There may be evidence that some government policies and practices may criminalise and/or deport victims and/or facilitate slavery. Services may be largely provided by IOs/NGOs with international funding, with limited government funding or in-kind support.
  • CC
    20 to 29.9
    The government has a limited response to modern slavery, with largely basic victim support services, a limited criminal justice framework, limited coordination or collaboration mechanism, and few protections for those vulnerable to modern slavery. There may be evidence that some government policies and practices facilitate slavery. Services are largely provided by IOs/NGOs with limited government funding or in-kind support.
  • C
    10 to 19.9
    The government response to modern slavery is inadequate, with limited and/or few victim support services, a weak criminal justice framework, weak coordination or collaboration, while little is being done to address vulnerability. There are government practices and policies that facilitate slavery. Services, where available, are largely provided by IOs/NGOs with little government funding or in-kind support.
  • D
    <0 to 9.9
    The government has a wholly inadequate response to modern slavery, and/or there is evidence of government-sanctioned modern slavery. However, countries in this category may be experiencing high levels of poverty and internal conflict that may prevent or hinder a response to modern slavery.

From the 'Less than Human' series. A large cargo boat is seen in Songkla Port, Thailand. 09/03/2014. Photographer Chris Kelly worked undercover to expose the link between prawns being sold in big name supermarkets, and the slaves who live and work on Thai fishing boats miles out to sea.

Photo credit, Chris Kelly

Access the Data

Walk Free’s data and the compilation of that data is proprietary and is protected by copyright and other intellectual property rights. At Walk Free, we welcome any efforts that will improve the estimation of the extent of modern slavery. We are keen to learn from and work with any person or government seeking to expose the prevalence of this crime. To that end, we are committed to sharing our data and methodology on terms applicable to its intended use, and as such our data is available under licence for both commercial and non-commercial use.

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Access the Data

Walk Free’s data and the compilation of that data is proprietary and is protected by copyright and other intellectual property rights. At Walk Free, we welcome any efforts that will improve the estimation of the extent of modern slavery. We are keen to learn from and work with any person or government seeking to expose the prevalence of this crime. To that end, we are committed to sharing our data and methodology on terms applicable to its intended use, and as such our data is available under licence for both commercial and non-commercial use.

Step 1 of 2

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